Chemistry of soil minerals. Part V. Low temperature hydrothermal transformations of kaolinite

Abstract

Raw kaolinite has been investigated as a possible starting material for low-temperature hydrothermal growth of zeolites and felspathoids. It proved to be convenient and versatile in this role, being readily transformed into a range of known and new zeolites and salt-inclusion felspathoids with a Si/Al ratio around 1·0, some of which have novel properties. Experiments were conducted at 80° using aqueous solutions of lithium, sodium, potassium, rubidium, and caesium hydroxides, sometimes in the presence of additional alkali-stable anions. Some quantitative aspects of the recrystallization reactions are discussed, as are the chemical and physical properties of representative compounds of each type synthesized.